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Removal of antibiotics from wastewater by advanced oxidation technologies
Macsek, Tomáš ; Rusník,, Igor (referee) ; Bodík,, Igor (referee) ; Hlavínek, Petr (advisor)
Antibiotics are substances that inhibit the growth of microorganisms and are widely used in modern medicine. High consumption of antibiotics correlates with their elevated occurence in sewage systems, from where they are further released into the environment. The threat of their occurrence in the environment is in triggering the formation and spread of antibiotic resistance. This thesis focuses on the removal of selected antibiotics and partly on the antibiotic resistance from wastewater by advanced oxidation processes (AOPs). AOPs are based on the creation of highly reactive hydroxyl radicals, which are able to oxidize even highly persistent substances. The thesis focuses on the purification of effluents from municipal wastewater treatment plants (WWTP), which are identified as the main source of pharmaceutical pollution in the environment, by AOPs mainly based on ozonation. These processes were tested under laboratory conditions on model water as well as under real conditions as the tertiary stage of the treatment at Brno-Modřice WWTP under various operating states. As the results of the performed experiments show, it could be concluded that the studied AOPs are capable of effective degradation of studied antibiotics from the treated medium. Under real conditions, the antibiotics sulfamethoxazole, trimethoprim, azithromycin and clarithromycin were monitored. Output concentrations in each operational state were achieved to be below the limit of detection for all four antibiotics. The application of AOPs based on ozonation as the tertiary step of the treatment also had a positive effect on the reduction of microbial contamination and antibiotic resistance. Within the pilot plant experiments, a reduction of up to 4 orders of magnitude of E.coli, coliform microorganisms and a reduction of their resistant strains in the range of 1.4 - 4.0 logs were observed, compared to the effluent from the WWTP.
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The function of ABCF proteins in bacteria
Mičke, Bianka ; Balíková Novotná, Gabriela (advisor) ; Lišková, Petra (referee)
Translation belongs to the most basic processes which happens in the living cells. It is the last step of proteosynthesis when genetic information encoded by the mRNA is transformed into the protein on a ribosome. Organisms have developed a wide range of mechanisms that can regulate it's needs. I focused on one of them - ABCF proteins. This protein group is a member of the ABC transporters superfamily but they haven't a transmembrane domain and their purpose is protect the ribosomes from antibiotics that bind 50S ribosomal subunit or interact with the ribosomes and influence ribosomal functions. Today, we can divide ABCF proteins into the two functional groups: antibiotic resistence proteins (ARE) and proteins with the regulatory functions. The translational regulatory function has been confirmed There is 45 ABCF protein subfamilies spread through the bacteries and eukaryotes but many essential informations like the structure and exact function of them are still missing. My bachelor thesis is analysis and summary of facts that are known about the bacterial ABCF proteins. Key words: ABCF proteins, antibiotic resistence, ARE, translational regulation, ribosome, translation, translational factors
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The importance of prompt diagnostic of MRSA patients and in the nosocomial environment of the Strakonice Hospital JSC
KUBIČKOVÁ, Andrea
Methicillin-resistant Staphylococcus aureus strains (MRSA) belong among the dangerous agents of nosocomial infections. Bacteremia-related mortality is reported 20-40%. Treatment of nosocomial infections is complicated and financially demanding. To reduce the risk for the patients, the introduction of anti-epidemic measures contributes for the effective searching of MRSA carriers and preventing the spread of resistant clones within the hospital, as well as rapid and reliable diagnosis of MRSA infections. The aim of this bachelor thesis is to describe the occurrence of MRSA strains in the Hospital Strakonice a.s. in 2012-2018 and to verify the usefulness of the Alere PBP2a SA Culture Colony Test for rapid MRSA diagnosis. The overall incidence of MRSA strains in the period of 2012-2018 was 3,27/1000 patients. The highest incidence of MRSA strains in reporting period was reported in 2018 (4,2/1000 patients). The higher incidence was detected in patients over 60 years of age and mainly in male patients. The wards where the highest number of new MRSA cases were recorded were surgical and internal ones, respectively. With the help of targeted screening from 29 up to 51 % new MRSA cases were revealed. The most common specimens were wound specimens (deep as well as superficial). In 2018, 74 isolated Staphylococcus aureus strains from clinically relevant materials such as blood and other body fluid specimens and tracheal aspirates were tested with the help of Alere PBP2a SA Culture Colony Test. 8 isolates were detetected positive for PBP2a protein and 66 were negative. Obtained results were in all cases confimed by the disc diffusion technique with the same results. The results of analysis were known within 6 minutes after the identification of Staphylococcus aureus strain and could have been actively reported to the physician. This lead to the significant speed-up of early initiation of appropriate targered antibiotic therapy. Alere PBP2a SA Culture Colony Test for rapid distinction between MRSA and MSSA Staphylococcus aureus strains reported 100% sensitivity as well as specificity. This test should be included in routine microbiological examination at ÚKMAS.
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Extensively resistant Acinetobacter baumannii in the Czech Republic: population genetic structure and mechanisms of resistance to carbapenems and aminoglycosides
Švandová, Ladislava ; Nemec, Alexandr (advisor) ; Melter, Oto (referee)
This study focuses on the question of the epidemiology of resistance to antibiotics in Acinetobacter baumannii, which is nowadays one of the most problematic bacterial patho- gens associated with failing antimicrobial therapy. Its aim was to define population-genetic properties, epidemiology and the nature of multidrug resistance for a sample of the current population of A. baumannii from Czechia. A total of 55 isolates were collected in eight medi- cal facilities in central Bohemia from October 2016 to May 2018. The isolates were assessed for their identity at the species, clonal and strain levels as well as resistance phenotype and genotype; they were classified into five clonal groups, each of which encompassed isolates that were likely to be epidemiologically related. The 55 isolates studied belonged, nearly exclusively, to global clone ECII, with 53 % of them forming a genetically relatively homoge- neous group characterized by extensive resistance to antibiotics (susceptible only to col- istin), the presence of genes encoding ArmA a OXA-23 (resistance to all aminoglycosides and carbapenems) and spread in all locations. The in-depth epidemiological analysis of isolates from the city of Příbram and its vicinity indicated the regional spread of two strains, one of which belonged to the...
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Subcellular localization of resistant proteins Vga(A)LC and Msr(A) using fluorescence microscopy
Nguyen Thi Ngoc, Bich ; Balíková Novotná, Gabriela (advisor) ; Lichá, Irena (referee)
Vga(A)LC and Msr(A) are clinically significant resistant proteins in staphylococci that confer resistance to translational inhibitors. They belong to ARE ABC-F protein subfamily, which is part of ABC transporters. Unlike typical ABC transporters, ABC-F proteins do not have transmembrane domains that are responsible for the transport of substances through the membrane. Therefore, they do not have characteristic transport function but regulatory or resistance function. Their mechanism of action on the ribosome has been described only recently, where these proteins displace the antibiotic from the ribosome. However, some aspects of their function are still unclear. For example, what is the function of the Vga(A) location on a membrane that has been detected in the membrane fraction but not in the ribosomal. In this work, using fluorescence microscopy, I observed subcellular localization of the Vga(A)LC-mEos2, Vga(A)LC-GFP and Msr(A)-eqFP650 resistant fusion proteins in live cells of S. aureus under different culture conditions . It has been shown that Vga(A)LC-GFP and Msr(A)-eqFP650 occur in a foci near the membrane. Depending on ATPase activity or the presence of an antibiotic, the localization of Msr(A)-eqFP650 in the cell changes from focal to diffuse, presumably on ribosomes, suggesting a...
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Development of antibiotic resistance in the region Písek in 2000-2010
MAREŠOVÁ, Lucie
This bachleor´ s dissertation is aimed to the developement of antibiotical resistance by choosed kinds of bacteria, particulary Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae in the region of Písek and also in the whole Czech Republic during the period 2000-2010. There is described matter of the antibiotical resistance, antimicrobial agents and also information about the EARS-Net system in the beginning of this work. The practical part contains the evaluation of resistance spread in the region of Pisek according to the data of clinical microbiology of Nemocnice Pisek, the spread of resistance in the Czech Republic according to the EARS-Net and also the consumption of individual groups of antibiotics according to the State Institute for Drug Control. Antibiotical resistance is spreading constantly, for example because of inappropriate usage of the antibiotics or insufficient information about pathogens that cause infectious diseases the most frequently.
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